# None 空,本身就是一个对象一个类型,表示不存在的概念

a = ''
b = False
c = []

print(a==None)
print(b==None)
print(c==None)

print(a is None)
print(b is None)
print(c is None)

print(type(None))
a
print(a is None)
print(not None)
print(not [])